【摘要】 煤层注水是综放开采回采巷道预防冲击地压的主要措施之一。为了研究含水煤样动态力学性质和力学参数，利用霍普金森压杆(SHPB)试验系统，对不同含水率的圆柱形煤样进行单轴冲击压缩试验，研究含水率和冲击速度对煤样动态应力-应变曲线、动态力学参数以及耗散能变化规律的影响。研究结果表明：(1)煤样动态力学参数与冲击速度和含水率有关。当煤样含水率一定时煤样动态抗压强度、动态弹性模量与冲击速度成正相关；而冲击速度一定时煤样动态抗压强度、动态弹性模量与含水率成负相关；(2)在冲击过程中煤样的损伤耗散能直接反映煤样中微裂隙发育程度，随着冲击时间的增加，煤样损伤耗散能增大，煤样坍塌破坏时损伤耗散能达到最大值。当含水率一定时煤样破坏耗散能与冲击速度成正相关；而冲击速度一定时煤样破坏耗散能与含水率成负相关；(3)损伤因子定义为煤样损伤耗散能与破坏耗散能的比率。基于煤样单轴冲击压缩试验结果，建立了煤样损伤体-黏弹性本构模型和本构关系，对不同含水率煤样动态应力-应变试验曲线进行理论拟合，理论拟合曲线与试验曲线拟合度高，因此理论曲线可用来表示单轴冲击压缩煤样的应力-应变关系。研究结论为冲击地压矿井深孔煤层注水预防冲击地压提供了理论基础。更多还原

【Abstract】 Coal seam water injection is one of the main measures to prevent coal bump in the gateways of a fully mechanized caving face. In order to study the dynamic mechanical properties and mechanical parameters of water-bearing coal specimens, the uniaxial impact compression tests of a certain number of cylindrical coal specimens with different moisture contents were carried out by using the split Hopkinson pressure bar(SHPB) test system. The effects of moisture content and impact velocity on the dynamic stress-strain curves, dynamic mechanical parameters, and dissipation energy of the coal specimens were studied. The results show that the dynamic mechanical parameters of coal specimens are related to the impact velocity and moisture content. When the moisture content of the coal specimens keeps constant, the dynamic compressive strength and dynamic elastic modulus of the coal specimens are positively correlated with the impact velocity. When the impact velocity keeps constant, the dynamic compressive strength and dynamic elastic modulus of the coal specimens are negatively correlated with the moisture content. The damage dissipation energy of the coal specimens during impact directly reflects the degree of micro-fracture development.With the increase of impact time, the damage dissipation energy of the coal specimens increases, and reaches the maximum when the coal specimens collapse. When the moisture content keeps constant, the failure dissipation energy of the coal specimens are positively correlated with the impact velocity. When the impact velocity keeps constant, the failure dissipation energy of the coal specimens is negatively correlated with the moisture content. The ratio of damage dissipation energy to failure dissipation energy of the coal specimens defined as its damage factor. Based on the uniaxial impact compression tests results of the coal specimens, the damage-viscoelastic constitutive model and constitutive relation were established. The dynamic stress-strain experimental curves of the coal specimens with different moisture content were theoretically fitted. The fitting degree between the theoretical and the experimental curves is rather high, so that theoretical curves can be used to represent the stress-strain relationship of uniaxial impact compression coal specimens.The conclusions provide a theoretical basis for the prevention of rockburst by the coal seam water injection into deep-holes in coal bump mines.更多还原